Fuel control mechanism



1957 w. F. ISLEY ETAL 3,338,224

FUEL CONTROL MECHANISM Filed May 4, 1965 2 Sheets-Sheet 1 251 FIG. 5

V Y INVENTORS FIG. .2. WALTER ISLEY DRUZYNSKI BY FRANK ATTORNEYS Aug.29, 1967 w. F. ISLEY ETAL FUEL CONTROL MECHANISM 2 Sheets-Sheet 2 IFiled May 4, 1965 C DRUZYNSKI ATTORNEYS v United States Patent 3,338,224FUEL CONTROL NLECHANiSM Walter F. Isley, Grosse Pointe, and Frank C.Druzynski, Birmingham, Mich., assignors to Continental Aviation andEngineering Corporation, Detroit, Mich., a corporation of Virginia FiledMay 4, 1965, Ser. No. 452,990 9 Claims. (Cl. 123-140) ABSTRACT OF THEDISCLOSURE A device for preventing the governor for an internalcombustion engine from actuating the delivery of an amount of fuel abovea predetermined setting at each throttle position and which permitsmaximum fuel delivery at idle and fully open positions of the throttleand permits a minimum fuel delivery at a throttle position approximatelyone-fourth of the distance between these two positions. This result is:produced by a drive plate connected with the throttle for rotationtherewith and which is connected with a fuel pump delivery limitingmeans through a pin and slot arrangement in which one pin engages in aslot to produce movement of the limiting means through a portion of therotation of the drive plate and another pin engages in another slot toproduce movement of the limiting means in an opposite direction throughrotation of the drive plate through the remaining arc.

The present invention relates to internal combustion engines,particularly fuel control means for such engines and more particularlyto an improved means adapted to be connected with the fuel pump for suchengines and operable to limit the maximum quantity of fuel which can bedelivered to the engine by the fuel pump at each throttle setting.

Governors are often provided on internal combustion engines for thepurpose of maintaining a constant engine speed at each throttle settingregardless of variations in engine load, Such devices therefore areoperable upon the engine load decreasing for instance to decrease theamount of fuel to the engine to thereby maintain a prededeterminedspeed. If the engine load should increase, then the governor actuatesmechanism to increase the fuel quantity delivered by the fuel pump tomaintain the constant speed desired. The problem encountered in suchfuel control systems is that when the engine is operating at part loadand an increased load is put upon the engine which would cause theengine to slow down or lug, the governor will automatically actuate thefuel pump to increase the quantity of fuel being delivered to the engineto maintain the original speed, even to the maximum quantity that thesystem is capable of delivering. Although this is a momentary andtemporary condition, it results in inefiiciency as well as undue wearespecially when such an engine is coupled to a transmission.Particularly, when an automatic transmission of the lock-up type iscoupled to the engine, the governor will in effect cause the engine toproduce full load power during the power shifts because shifting throughthe gears does not occur until the engine is lugged down to the speedshift point. During the power shift, the engine speed increases, due tothe excess fuel being delivered by the governor, severe loading isproduced on the clutches, gears and the shift mechanism of thetransmisison to thereby produce wear, reduce the durability of themechanism, and cause harsh sounding and feeling shifting.

Heretofore means have been provided for preventing the governor fromincreasing engine speed beyond a given value at each throttle posit-ion.In this way the govenror is prevented from momentarily increasing fueldelivery to the maximum upon each increase in engine load. The problem,however, with such prior art systems has been produced by the fact thatengine characteristics do not permit the provision of a limiting meanswhich limits the maximum fuel the system can deliver at each throttleposition in a straight line function. As the throttle positionapproaches the idle position from a position approximately one-fourthfully open it has been found that it is necessary to permit the governorto increase the amount of fuel delivered by the fuel pump at a change inthe engine load to insure proper recovery of the engine and that at theidle position it is necessary to permit the governor to actuate the pumpto deliver substantially the maximum amount of fuel the system iscapable of delivering in order to insure that the engine will properlyrecover at a substantial increase in engine load at that throttleposition. Therefore any governor limiting means must permit the governorto deliver maximum fuel at the idle position and fully opened positionsand must diminish the amount of fuel that the system is permitted todeliver from these positions toward a minimum amount which is permittedat a throttle position substantially one-fourth of the way between idleand the fully opened position of the throttle.

The present invention provides a limiting means operable to prevent agovernor from actuating the delivery of an amount of fuel above apredetermined setting at each 7 provided are operable to increase thepredetermined set-- ting from this intermediate throttle position to afully open throttle position so that sufficient fuel is available forproper recovery of the engine at all positions of the throttle.

It is an object then of the present invention to provide a governorlimiting means operable to prevent the governor from actuating a maximumfuel delivery to the engine each time engine load increases at apredetermined throttle position other than idle and full load.

It is another object of the present invention to provide limiting meansfor controlling the operation of a governor which is operable to permitthe governor to actuate delivery of maximum fuel at the idle positionsof the throttle and to permit a slowly diminishing amount of fuel to bedelivered as the throttle approaches a position substantially one-fourthof the way between idle and fully open and to permit a slow increase inthe amount of fuel permitted to be delivered as the throttle approachesthe fully opened posit-ions from the intermediate position.

It is a further object of the present invention to reduce loading on thegears of transmissions and harshness of shifting for governor controlledinternal combustion engines by providing means limiting the amount offuel I which can be delivered to the engine at each part throttlesetting whereby engine speed is not permitted to momentarily increase toa maximum value as the engine'load is increased through operation of thetransmission.

Still further objects and advantages of the present invention will bereadily apparent to one skilled in the art upon reference to thefollowing drawings in which like reference characters refer to likeparts throughout the several views and in which FIG. 1 is a diagrammaticview illustrating the relation of a preferred fuel limiting means to afuel control system of an internal combustion engine.

FIG. 2 is a fragmentary cross-sectional view of a preferred fuellimiting means of the present invention as seen substantially from line22 of FIG. 3 and with portions removed for purposes of clarity.

FIG. 3 is a cross-sectional view of the limiting device illustrated inFIG. 2 and with portions removed for purposes of clarity.

FIG. 4 is a view similar to FIG. 3 but illustrating another preferredoperating position of the limiting means of the present invention.

FIG. 5 is a fragmentary cross-sectional view of the structure shown inFIGS. 3 and 4 but illustrating yet another operating position of thelimiting means of the present invention.

Now referring to the drawings for a more detailed description of thepresent inveniton, FIG.'1 illustrates diagrammatically an internalcombustion engine having a fuel pump 12 preferably drivingly connectedthereto and operable to deliver fuel to the engine 10 from a fuel tank14. A fuel density control means is illustrated diagrammatically at 1-6as being connected to the fuel pump 12 and the fuel tank 14 by conduits18 and 20 respectively. As will be more apparent as the descriptionproceeds, the fuel density control means 16 is not a necessary part ofthe present invention and has been more carefully described and claimedin our copending application, Ser. No. 281,715, filed May 20, 1963 andnow Patent No. 3,204,623.

A governor 22 is preferably connected to the engine 10 as shown,'todetect engine speed and is connected by a linkage 24 to a throttle 26and by linkage 30 to the fuel pump 12.

The throttle 26 is positioned to maintain the desired engine speed. Thelinkage 24 actuates the governor which senses engine speed and throughlinkage 30' controls the fuel pump 12 to maintain a desired engine speedregardless of changes in engine load. The engine 10 illustrated ispreferably a multi-fuel type although as the description proceeds itwill be apparent that other engines can be used as well. The fuellimiting means 32 as will be described in greater detail below, isconnected by linkage 28 to the full load stop (not shown) of the fuelpump 12 and by linkage 25 to the throttle 26 to prevent the governor 22from actuating the fuel pump 12 to deliver fuel to the engine 10 above apredetermined maximum rate for each position of the throttle 26. Becausethe engine 10 is preferably of a multi-fuel type the fuel densitycontrol means 16 acts to regulate the full load stop of the fuel pump 12in response to variations in the viscosity of the fuel being deliveredto the engine 10 substantially as described in our aforementionedcopending application.

Now referring to FIGS. 2-5 for a more detailed description of thelimiting device 32 of the present invention, the device 32 is thereinillustrated as comprising a housing '34 defining an open chamber 36. Thefuel density control means 16 is preferably mounted on top of thelimiting means 32 to close the chamber 36. As more completely describedin our aforementioned copending application, the fuel viscosity controldevice 16 includes a rod 38 which is axially movable in response tochanges in the fuel viscosity of the fuel being delivered to the engine10 and which is pivotably connected as at 40 to a forked member 42. Theforked member 42 is pivotably connected at 44 to a lever arm 46. A wedgeblock 48 is secured to a pin member 50 which is in turn axiallyadjustably carried in an extension of the housing 52 of the fuel densitycontrol means. 16. A guide surface 54 is provided-on the housing 52 andan extension 56 of the wedge block 48 slidably engages the guide surface54. Nut members 58 and a spring member 60 permit axial adjust ment ofthe pin member 50 to move the wedge block 48 along the surface 54.

As can best be seen in FIG. 2 a shaft 62 is rotatably carried in thehousing 34 and extends into the chamber 36 of the limiting means 32. Ascan best be seen in FIGS. 3 through 5 a drive plate 64 is secured to theshaft 62 for rotation therewith and comprises at least two spaced armportions 66 and 68 each carrying a pin member 70 and 72 respectively. Alink 74 is provided with an enlarged opening 76 which encompasses theshaft 62 but which is not in engagement therewith as illustrated, andelongated slots 78 and 80 through which the pins 70 and 72 arerespectfully inserted. The upper portion of the link 74 is bent as shownat 82 to provide a seat for a spring 84 secured to the housing 34 andurging the link member 74 downwardly into engagement with one or both ofthe pins 70 and 72. The upper portion of the link member 74 is pivotablysecured as at 86 to a center wedge member 88. The shaft 62 extendsexteriorly of the housing 34 as shown in FIG. 2, and is rotatable bymeans of an arm adapted for connection to the throttle 26 by the linkage25.

The linkage 28 is pivotally connected'to a pivotally mounted arm 89. Thearm 89 is provided with a nose cam 90 which engages with an inclinedface portion of the lever arm 46. The center wedge 88 is provided withopposite inclined faces 92 and 94 which respectively engagecomplementary faces 96 and 98 provided on the wedgeblock 48 and leverarm 46 respectively so that the center wedge 88 is positionedintermediate the wedge block 48 and the lever arm 46. In the embodimentillustrated, movement of the arm 89 to the right as seen in FIG. 3actuates the full load stop of the fuel pump 12 through the linkage 28to decrease the quantity of fuel which can be delivered to the engine10. Pivotable movement of the arm 89 to the left as seen in FIG. 3actuates the full load stop of the fuel pump 12 through the linkage 28to increase the amount of fuel which can be delivered to the engine 10.The nose cam 91 of the arm 89 engages in the inclined face 100 of thelever arm member 46 so that axial movement of the rod 38 in response tochanges in the viscosity of the fuel being delivered to the engine 10produces a corresponding pivotal movement of the arm 89 to vary the fullload stop of the fuel pump 12.

It is apparent that movement of the center wedge 88 along the surfaces96 and 98 will produce an outward or inward movement of the surface 100of the arm member 46 to move the linkage 28 through the nose cam 90 andarm member 89 to thereby vary the position of the full load stop of thefuel pump 12.

It is apparent that the movement of the throttle 26 pro- 7 duces arotation of the shaft 62 and a corresponding movement of the drive plate64 so that the position of the arm 7 portions 66 and 68 will changedepending upon the position of the throttle 26. With the throttle in aposition substantially one-fourth of the way intermediate an idleposition and a fully open position the shaft 62 will be rotated toposition the drive plate 64 and the arm portions 66 and 68 as shown inFIG. 3. In this position both pins 70 and 72 engage the upper portionsof the link 74 defining the slots 78 and 80 respectively so that thelink 74 and the center wedge 88 are in the lowermost possible position.

In this position the arm member 89 is urged to pivot toward the right asshown in FIG. 3 the maximum distance for a given position of the rod 38so that the full load stop on the fuel pump 12 is adjusted to itsminimum full load position that the particular engine will tolerate forgood recovery for the particular fuel being used. The governor will notbe permitted then to actuate the fuel pump 22 to deliver more fuel thanthe predetermined setting produced by the linkage 30 regardless ofchanges in load conditions.

Further opening of the throttle 26 produces a counterclockwise rotationof the shaft 62 toward the position illustrated in FIG. 4.Counter-clockwise rotation of the shaft 62 and drive member 64 causesthe pin 70 to disengage from the end of the 'slot 78 in the link 74 butthe pin 72 remains engaged in the upper portion of the slot 80 andcauses the link member 74 and the center wedge 88 to be moved upwardlyto thereby move the arm member 89 to the left as seen in FIG. 4 toadjust the full load stop of the fuel pump 12 to permit the governor todeliver a greater quantity of fuel to the engine 10. It is apparent thenthat over approximately three fourths the upper range of the throttle 26the link 74 is moved upwardly to adjust the full load stop of the fuelpump 12 and to thereby adjust the upper limits of maximum fuel that thefuel pump 12 is permitted to deliver to the engine in response toactuation by the governor 22. Over this range the limit is substantiallya straight line function. This prevents the governor 22 from momentarilyactuating the fuel pump 12 to deliver the maximum quantity it is capableof delivering each time engine speed is decreased at a predeterminedthrottle setting because of an increase in engine load at that setting.-

It has been found that as engine speed is decreased through a range ofthrottle positions from idle to approximately one fourth fully opened,an increasing amount of available fuel is required to insure properrecovery of the engine and in fact at idle the governor 22 must becapable of actuating the fuel pump 12 to deliver substantially themaximum quantity it is capable of delivering so that any limiting meansmust adjust the full load stop of the fuel pump 12 to a substantiallyfully opened position at idle position of the throttle. The particularlimiting means of the present invention produces this result.

As the throttle 26 is moved from the position illustrated in FIG. 3toward an idle position the shaft 62 is rotated in a clockwise directionto rotate the drive plate 64 and the arm portions 66 and 68 toward theposition shown in FIG. 5. As the drive plate 64 is rotated, the pinmember 70 engages in the upper portion of the slot 78 to move the link74 and the center wedge 88 upwardly and to thereby adjust the full loadstop of the fuel pump 12 toward the maximum value so that at idleposition the link 74 and center wedge 88 are at their upper-mostposition and the full load stop of the pump 12 is at a positionpermitting maximum fuel delivery to the engine.

Thus as the throttle 26 is moved from the idle position toward the fullyopen position, the drive plate 64 and pin members 70 and 72 are movedfrom the position shown in FIG. 5 toward the position shown in FIG. 3.The drive late 64 moves in a counter-clockwise direction to produce arelative movement of the pin member 70 away from the upper portion ofthe slot 78 and of the pin member 72 toward the upper portion of theslot 80. The spring member 84 maintains contact between the pin member70 and the upper portion defining the slot 78 so that the link 74 ismoved downwardly during initial rotation of the drive plate 64.

Because the slot 80 is of a lesser length than slot 78 and is positionedwith its upper portion below the upper portion of slot 78 the pin 72will be brought into engagement with the upper portion of slot 80 beforepin 70 is moved into engagement with the lower portion of slot 78. Atthis position both pins engage link 74 and the link 74 is in itslowermost position. It is apparent that if both slots 78 and 80 were ofthe same length, this position would be produced upon the throttle 26being positioned substantially midway between idle and fully open.

Further counterclockwise movement of the drive plate 64 causes the pin72 to move the link 74 upwardly toward the maximum position shown inFIG. 4.

It is apparent that the limiting means of the present invention providesan efiective means of limiting the tendency of a governor to actuate thefuel pump to produce maximum fuel delivery each time engine load isincreased at a particular throttle setting. The limiting means of thepresent invention imposes a maximum value at each throttle setting abovewhich the governor cannot actuate the fuel pump. The particular slottedlink 74 and pins 70 and 72 of the present invention are operable toprovide position. This permits sufficient fuel quantity availability atand around idle to insure that the engine will properly recover asheretofore explained.

It is also apparent that although we have described but one embodimentof our invention many other changes and modifications can be madewithout departing from the spirit of the invention as expressed by theappended claims.

We claim:

1. In combination with a member adapted for reciprocating movementbetween a first position and a second position,

(a) a drive plate and means for selectively rotating said drive platebetween a first drive plate position, a second drive plate position, anda drive plate position intermediate said first and second position,

(b) means connecting said member and said drive plate and operable uponrotation of said drive plate from said first drive plate position towardsaid intermediate drive plate position to move said member from saidfirst position toward said second position, and operable upon furtherrotation of said drive member from said intermediate drive platepositioned toward said second drive plate position to move said memberfrom said second position toward said first position,

(c) the improvement being said last mentioned means comprising a firstpin member and a second pin member and means connecting said drive plateand said member through only said first pin member at said first driveplate position and connecting said drive plate and said member throughboth of said pin members at said intermediate drive plate position, andconnecting said drive plate and said member through only said second pinmember at said drive plate position, said pin members being positionedon said drive plate and said connecting means comprising a pair of slotsprovided in said member and receiving said pin members.

2. The combination as defined in claim 1 and in which said slots areelongated and are of different lengths.

3. The combination as defined in claim 1 and including means urging saidmember into engagement with said pin members.

4. In an internal combustion engine having a fuel pump and a throttle, ameans for connecting said throttle and said fuel pump to regulate themaximum amount of fuel which can be delivered by said fuel pump to saidengine at each position of said throttle, said means comprising,

(a) a link member adapted for reciprocating movement between a firstposition and a second position and means connecting said link member tosaid fuel pump and operable to permit maximum fuel delivery by said fuelpump at said first position of said link member and to permit apredetermined minimum fuel delivery at said second position of said linkmember,

(b) a rotatably mounted drive plate and means connecting said driveplate and said throttle and operable to rotate said drive plate inresponse to changes in the position of said throttle, said drive platebeing rotatable between a first drive plate position corresponding tothe idle position of said throttle, a second drive plate positioncorresponding to the fully opened position of said throttle, and a driveplate position intermediate said first and second drive plate po sitionsand corresponding to a position intermediate said idle and fully openedpositions of said throttle,

(c) the improvement comprising means connecting said link and said driveplate and operable upon rotation of said drive plate from said firstdrive plate positioned toward said intermediate drive plate positionedto move said link member from said first position toward said secondposition and operable upon further rotation of said drive plate fromsaid intermediate drive plate position toward said second drive plateposition to move said link member from said second position toward saidfirst position.

5. The combination as defined in claim 4 and in which said last meanscomprises a first pin member and a second pin member and meansconnecting said drive plate and said link member through only said firstpin member at said first position of said drive plate and connectingsaid drive plate, and said link member through both of said pin membersat said intermediate position of said drive plate, and connecting saiddrive plate and said link member through only said second pin member atsaid second position of said drive plate.

6. The combination as defined in claim 5 and in which said pins arepositioned on said drive plate and said last mentioned means comprisesslots provided in said link member.

9. The combination as defined in claim 4 and in which said intermediateposition of said drive plate corresponds to a position of said throttlesubstantially one-fourth of the way between idle and fully open. 7

References Cited UNITED STATES PATENTS 2,771,280 11/1956 Andis 74107 X2,818,053 12/1957 Shallenberg 123-140 3,130,599 4/1964 Haas 74526LAURENCE M. GOODRIDGE, Primary Examiner.

1. IN COMBINATION WITH A MEMBER ADAPTED FOR RECIPROCATING MOVEMENTBETWEEN A FIRST POSITION AND A SECOND POSITION, (A) A DRIVE PLATE ANDMEANS FOR SELECTIVELY ROTATING SAID DRIVE PLATE BETWEEN A FIRST DRIVEPLATE POSITION, A SECOND DRIVE PLATE POSITION, AND A DRIVE PLATEPOSITION INTERMEDIATE SAID FIRST AND SECOND POSITION, (B) MEANSCONNECTING SAID MEMBER AND SAID DRIVE PLATE AND OPERABLE UPON ROTATIONOF SAID DRIVE PLATE FROM SAID FIRST DRIVE PLATE POSITION TOWARD SAIDINTERMEDIATE DRIVE PLATE POSITION TO MOVE SAID MEMBER FROM SAID FIRSTPOSITION TOWARD SAID SECOND POSITION, AND OPERABLE UPON FURTHER ROTATIONOF SAID DRIVE MEMBER FROM SAID INTERMEDIATE DRIVE PLATE POSITIONEDTOWARD SAID SECOND DRIVE PLATE POSITION TO MOVE SAID MEMBER FROM SAIDSECOND POSITION TOWARD SAID FIRST POSITION, (C) THE IMPROVEMENT BEINGSAID LAST MENTIONED MEANS COMPRISING A FIRST PIN MEMBER AND A SECOND PINMEMBER AND MEANS CONNECTING SAID DRIVE PLATE AND SAID MEMBER THROUGHONLY SAID FIRST PIN MEMBER AT SAID FIRST DRIVE PLATE POSITION ANDCONNECTING SAID DRIVE PLATE AND SAID MEMBER THROUGH BOTH OF SAID PINMEMBERS AT SAID INTERMEDIATE DRIVE PLATE POSITION, AND CONNECTING SAIDDRIVE PLATE AND SAID MEMBER THROUGH ONLY SAID SECOND PIN MEMBER AT SAIDDRIVE PLATE POSITION, SAID PIN MEMBERS BEING POSITIONED ON SAID DRIVEPLATE AND SAID CONNECTING MEANS COMPRISING A PAIR OF SLOTS PROVIDED INSAID MEMBER AND RECEIVING SAID PIN MEMBERS.